This invention relates generally to machining techniques, and more specifically to methods and apparatus for ultrasonic machining.
At least some known components include features that require ultrasonic machining. More specifically, complex-shaped components, for example gas turbine engine blades, often have geometric constraints which may limit the use of conventional machining methods. For example, blind holes which have non-circular and/or tapered cross-sections may be inaccessible to conventional machining heads. Typically, ultrasonic machining is a “directional” machining process, wherein to optimize performance an amplitude of a sonic vibration is aligned with a direction of desired material removal. However, aligning the sonic vibration amplitude may limit the usefulness of ultrasonic machining when applied to complex-shaped components.
At least some known ultrasonic machining methods use trial and error to machine complex-shaped components. More specifically, in at least some known ultrasonic machining methods, various curved or irregularly-shaped tuning forks or cutters are fabricated, and an amplitude of vibration is bent or redirected into alignment with geometry of the tuning fork or cutter. However, bending or redirecting an amplitude into alignment with the geometry of the tuning fork or cutter may inhibit the amount of energy directed to a machining surface or material, and thus may limit the effectiveness of the ultrasonic machining.